Set a "metrics_client_id" crash key instead of "guid" on Mac OS X

chrome/common/chrome_switches.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Defines all the command-line switches used by Chrome.
 
 #ifndef CHROME_COMMON_CHROME_SWITCHES_H_
 #define CHROME_COMMON_CHROME_SWITCHES_H_
 
 #include "build/build_config.h"
@@ skipping 350 matching lines @@
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
 extern const char kMigrateDataDirForSxS[];
 #endif
 
 #if defined(OS_MACOSX)
 extern const char kAppsKeepChromeAliveInTests[];
 extern const char kHostedAppQuitNotification[];
 extern const char kDisableHostedAppShimCreation[];
 extern const char kDisableSystemFullscreenForTesting[];
 extern const char kRelauncherProcess[];
+extern const char kMetricsClientID[];
 #endif
 
 #if defined(OS_WIN)
 extern const char kEnableCloudPrintXps[];
 extern const char kEnableProfileShortcutManager[];
 extern const char kForceDesktop[];
 extern const char kForceImmersive[];
 extern const char kRelaunchShortcut[];
 extern const char kViewerLaunchViaAppId[];
 extern const char kWaitForMutex[];
@@ skipping 25 matching lines @@
 #if defined(OS_CHROMEOS)
 bool PowerOverlayEnabled();
 #endif
 
 // DON'T ADD RANDOM STUFF HERE. Put it in the main section above in
 // alphabetical order, or in one of the ifdefs (also in order in each section).
 
 }  // namespace switches
 
 #endif  // CHROME_COMMON_CHROME_SWITCHES_H_